As the 19th century came to a close, physicists were feeling pretty satisfied with the state of their science. The great edifice of physical theory seemed complete. A few minor experiments remained to ...

In the late 1800s, no one knew what light was. Everyone knew it behaved like a wave some of the time, but all waves need to travel through some propagation medium. This propagation medium was called ...

Brendan Foster describes renewed interest in the luminiferous aether (2 November, p 32). For all its shortcomings, the aether was one of the most productive scientific ideas of all time. Many ...

This is an easier one than dark matter vs. modified gravity. As mentioned, I'm going to be on Science Friday today, and they asked me to contribute a guest blog post, which I'm cross-posting below.

“…upon this simple system of many colors is based the manifold and infinitely varied investigation of all things.” —Zosimos of Panopolis (ca. 250 CE ...

LIGO announced today that they have detected gravitational waves from a black hole merger. If verified it will be the ultimate confirmation of Einstein's theory of general relativity. But what are ...

Albert Michelson was a Polish immigrant who grew up in the hard-scrabble atmosphere of the California gold rush. He relied on an appeal to then-President Ulysses Grant to gain admission to the Naval ...